1. Field of the Invention
The present invention relates to a control device of an inverted pendulum type vehicle capable of moving on a floor surface.
2. Description of the Related Art
An inverted pendulum type vehicle has a base body assembled with a travelling motion unit capable of travelling on a floor surface, an actuator which drives the travelling motion unit and a payload supporting part for transporting a subject which is capable of freely tilting with respect to the perpendicular direction. In order to maintain a tilt angle of the payload supporting part at a desired tilt angle (to prevent the payload supporting part from falling down), it is necessary for the inverted pendulum type vehicle to move the travelling motion unit by displacing a fulcrum of the inverted pendulum.
As a control technology of this type of the inverted pendulum type vehicle, for example, the one disclosed in Patent Document 1 (Patent No. 3070015) had been proposed by the present applicant.
In the Patent Document 1, there is disclosed a control technology of an inverted pendulum type vehicle in which a base body of a vehicle assembled with a payload supporting part for transporting a subject, namely, an occupant, is provided so as to be freely tiltable about two axes, specifically one axis in a longitudinal direction and the other axis in a lateral direction, with respect to the travelling motion unit having a ball shape. In the control technology, a driving torque of a motor is sequentially determined so as to approximate a difference between a measured value of a tilt angle of the base body (=tilt angle of the payload supporting part) and a desired tilt angle and a difference between a measured value of a velocity of the motor as an actuator unit (and consequently a travelling velocity of the travelling motion unit) and a desired velocity to 0. Thereafter, the travelling motion of the travelling motion unit is controlled via the motor according to the determined drive torque.
The present applicant further proposes vehicles capable of functioning as the inverted pendulum type vehicle, such as those disclosed in Patent Document 2 (Published PCT International Application WO/2008/132778) and Patent Document 3 (Published PCT International Application WO/2008/132779).